Implantable Interface for a Medical Device System

ABSTRACT

An implantable interface system for a medical device system providing selective interconnectivity between conduits and therapy elements. The interface system contains connecting elements that each provide a robust connection between a selected conduit and a selected therapy element. The interface system enables the use of a surplus of therapy elements so that treatment to the same site (in the case of electrode migration or failure), or to different sites but within the spatial domain of the interface&#39;s elements may be delivered through the spare/excess therapy elements without the need for additional major surgical procedures.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. application Ser. No.11/414,736 filed on Apr. 28, 2006, which is incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

The invention relates to the field of implantable systems for selectingtherapy elements to monitor the status of and/or delivery therapy totissue within a patient. More particularly, the invention providesconvenient, non-invasive or minimally-invasive selection of a subsetfrom a surplus of therapy elements previously implanted into tissue forconnection with a (subset) of device conduits. The interface system mayenable communication in a bi-directional manner (from device to tissueand from tissue to device) using the same therapy element(s) and/orconduits(s).

BACKGROUND

Electrical stimulation of the brain has been used to treat any number ofneurological disorders including, for example, pain and movementdisorders. Electrical leads having many electrodes are implanted in thebrain such that one or more cathodal electrodes and one or more anodalelectrodes are in optimal locations to produce benefits or to minimizeundesirable side effects. An implantable pulse generator (IPG) generatessignals to deliver electrical stimulation to the brain tissue via theelectrodes. These electrodes or electrodes in other leads, may be alsoused to record electrical signals that, once adequately processed andanalyzed using implantable or portable devices, may be used to monitorthe state of the tissue or organ and to also deliver a therapy when thisstate is approaching abnormalcy. Additionally or alternatively, sets ofinputs catheters carrying drugs may be selectively connected to sets ofoutput catheters for drug delivery to surrounding tissue.

Depending on the disorder, sensing and or therapy systems may utilize alarge number of electrodes or catheters to monitor and treat thedisorder. Accordingly, the treating physician may configure the systemwith a spatial configuration of cathodes and anodes or of catheters thatis best suited for any particular disorder or patient. If required, thetreating physician may later optimize the electrode or catheter spatialconfiguration by selecting different electrodes or catheters from thoseoriginally chosen. Also, leads/electrodes or catheters may shift ormigrate (in reference to the intended monitoring or therapy target)after being implanted, the chosen electrodes or catheters may “break,”or the intended target site may change over time. To either improve thetherapeutic benefits or to replace malfunctioning or off-targetelectrodes or catheters in prior-art implanted medical devices oftenrequires a major surgical procedure.

Therefore, it is desirable to: a) implant more sensing and/or therapyelements than those actually used (i.e., those which sense electricalsignals and/or through which currents or drugs are actually delivered totissue) so that, by switching certain elements OFF and others ON,electrical currents or drugs continue to be delivered to the intendedtarget or to a new one located within the spatial domain/reach of thesensing and/or therapy elements; and b) accomplish these tasks withoutfurther surgery.

Therefore, there exists a need in the art for implantable interfaces forelectrical monitoring and/or stimulation and/or for drug delivery havinga plurality/surplus of electrodes or catheters that may be selectivelychosen and coupled to monitor tissue electrical signals and deliverelectrical stimulation or drugs to desired neural tissue, withoutexceeding or violating size constraints for implantability and/orwithout requiring additional surgeries.

SUMMARY

The following represents a simplified summary of some embodiments of theinvention in order to provide a basic understanding of various aspectsof the invention. This summary is not an extensive overview of theinvention. It is not intended to identify key or critical elements ofthe invention or to delineate the scope of the invention. Its solepurpose is to present some embodiments of the invention in simplifiedform as a prelude to the more detailed description that is presentedbelow.

In accordance with aspects of the invention, an implantable interfacesystem for a medical device system is disclosed. The interface systemenables the flexible and efficient utilization of a surplus of sensingand/or therapeutic elements (i.e., therapy elements), allowing anoptimal subset of these elements to be selected for use (and latermodified if necessary) without major surgery that would otherwise berequired to reposition, replace or activate more therapy elements. Theinterface system thus enables, for example, an increase in the availablesize of the electrical field or of the area to which drugs aredelivered, while keeping the size of the hardware/device small so thatit can be safely and ergonomically implanted. The interface systemprovides selective, re-programmable interconnectivity between aplurality/surplus of inputs and a plurality/surplus outputs that may beoperated bi-directionally (inputs become outputs and vice-versa)depending on the application. These therapy elements may be implantedinto or near an organ of a patient, for example, a brain. The interfacesystem enables the use of a surplus of therapy elements so thattreatment to the same site (in the case of electrode migration orfailure), or to different sites but within the spatial domain of theinterface's elements may be delivered through the spare/excess therapyelements without the need for additional major surgical procedures. Forexample, without further major surgery, the interface system may be usedto select from a surplus of therapy elements to selectively determinewhich subset is used to provide input to a monitoring device.Alternatively, the interface system also enables selection of a subsetof therapy elements (e.g., stimulation contacts or catheters) to be usedas outputs to deliver therapy (e.g., stimulation or drugs, respectively.

In an embodiment, the interface system may include two plates. A firstplate may be coupled to the conduits via one or more first plate contactpoints. The second plate may be coupled to the therapy element via oneor more second plate contact points. One or more connecting elements maybe positioned between the first and second plates, wherein eachconnecting element provides a robust electrical connection between aselected conduit and a selected therapy element. In an embodiment, theconnecting element provides physical contact between the first platecontact point associated with the selected conduit and the second platecontact point associated with the selected therapy element. In anembodiment, a middle plate may be provided between the first and secondplates to facilitate positioning of the connecting elements. In anembodiment, a spring mechanism may also be provided within the interfacesystem to ensure adequate electrical connection provided by theconnecting elements. The interface system may be encapsulated in ahousing that may include a cover such as a membrane so as to ensure afluid-tight seal.

In accordance with another aspect of the present invention, one or morevalves may be provided to couple one or more inlet tubes with aplurality of delivery/outlet tubes. In an embodiment, an inlet tube maybe adjustably connected to a plurality of delivery tubes. A series ofvalves may be coupled together in a module so that fluid from areservoir may be selectively delivered to one or more delivery tubes soas to delivery fluid to the patient in a desired two dimensional orthree dimensional pattern. The amount of fluid being delivered to eachdelivery tube may be adjustable. The system can also be usedbi-directionally, for example, to sample fluids from a plurality ofsites and store them in chambers.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and not limitedin the accompanying figures in which like reference numerals indicatesimilar elements and in which:

FIG. 1 schematically depicts an implantable medical device systemproviding electrical stimulation or some other form of therapy to thebrain and/or sensing a characteristic of the brain.

FIG. 2 depicts an implantable interface system in accordance with one ormore aspects of the present invention.

FIG. 3 shows one of many possible shapes of an implantable interfacesystem and of its inputs and outputs in accordance with one or moreaspects of the present invention.

FIGS. 4 and 5 illustrate an embodiment of an implantable interfacesystem implanted within a skull of a patient in accordance with one ormore aspects of the present invention.

FIG. 6 is a partial exploded cross-sectional view of the variouscomponents of an implantable interface system in accordance with one ormore aspects of the present invention.

FIG. 7 is a schematic diagram illustrating one of many possible ways ofconnecting elements to selectively interconnect certain inputs tocertain outputs within an implantable interface system in accordancewith one or more aspects of the present invention.

FIG. 8 is a simplified cross sectional view of an implantable interfacesystem in accordance with one or more aspects of the present invention.

FIGS. 9 a-9 b illustrate an embodiment of an access template system inaccordance with one or more aspects of the present invention.

FIGS. 10 a-c illustrate embodiments of access templates in accordancewith one or more aspects of the present invention.

FIG. 11 illustrates yet another embodiment of an access template inaccordance with one or more aspects of the present invention

FIG. 12 illustrates an embodiment of a top and bottom plate inaccordance with one or more aspects of the present invention.

FIG. 13 illustrates a top and bottom plate having a conduit lead to linkto the multiple controller extensions in accordance with one or moreaspects of the present invention.

FIGS. 14-15 illustrate an embodiment of a connecting element/mechanismin accordance with one or more aspects of the present invention.

FIG. 16 illustrates an alternative embodiment of a connecting element inaccordance with one or more aspects of the present invention.

FIG. 17 illustrates an embodiment of a flow module in accordance withone or more aspects of the present invention.

FIGS. 18 a-18 c illustrate an embodiment of a valve in differentconfigurations in accordance with one or more aspects of the presentinvention.

FIGS. 19 a-19 d illustrate cross-sections of an embodiment of a valve indifferent configurations in accordance with one or more aspects of thepresent invention.

FIG. 20 illustrates a cross-section of embodiment of a valve configuredto provide variable flow in accordance with one or more aspects of thepresent invention.

FIG. 21 illustrates a cross-section of an embodiment of a valveconfigured to be installed in series in accordance with one or moreaspects of the present invention.

FIG. 22 illustrates an embodiment of two flow modules configured to beused together in accordance with one or more aspect of the presentinvention.

FIG. 23 illustrates an embodiment of a flow module with multiple inputsin accordance with one or more aspects of the present invention.

FIG. 24 illustrates a system configured to provide an adjustable fluiddelivery in accordance with one or more aspects of the presentinvention.

FIGS. 25 a-25 b illustrate an embodiment of a delivery tube capable ofdelivering an adjustable flow rate to adjustable/different sites inaccordance with one or more aspects of the present invention.

DETAILED DESCRIPTION

Aspects of the invention may be embodied in any implantable medicaldevice system wherein a component of the system is to be implantedwithin a patient to monitor tissue electrical signals and/or providetherapy in the form of electrical stimulation or drug delivery. Theimplantable interface system discussed herein may have physicalattributes (length/width/thickness, consistency and weight) that willallow implantation avoiding or minimizing the potential for causinginjury to the brain or spinal cord or discomfort to the patient, whilemaximizing precision and degree of contact between the device elementsand the therapy targets or sites. An embodiment of the invention mayutilize various treatment therapies for treating nervous systemdisorders. Treatment therapies can include any number of possibilitiesalone or in combination including, for example, electrical stimulation,drug delivery and/or providing a warning of impending undesirable eventsto the patient or to caregivers.

Each of these treatment modalities may be operated using closed-loopfeedback control or using open-loop therapy. Such closed-loop feedbackcontrol techniques receive one or more signals that carry informationabout a symptom or a condition of a nervous system disorder. Suchsignals can include, for example, electrical signals (such as EEG, ECoGand/or EKG), bio-chemical signals (such as change in quantity ofneurotransmitters), temperature signals, pressure signals (such as bloodpressure, intracranial pressure or cardiac pressure), respirationsignals, heart rate signals, pH-level signals, and/or peripheral nervesignals (cuff electrodes on a peripheral nerve). Such signals may berecorded using one or more monitoring elements such as monitoringelectrodes or sensors. For example, U.S. Pat. No. 6,227,203, assigned toMedtronic, Inc., provides examples of various types of monitoringelements that may be used to detect a symptom or a condition or anervous system disorder and responsively generate a neurological signal.

In accordance with one set of embodiments, the implantable interfacesystem is associated with a therapy delivery element or a monitoringelement or a combination of both (dual function). FIG. 1 schematicallyrepresents these embodiments and depicts an implantable medical devicesystem 100 that provides treatment therapy to the brain and/or monitorsa characteristic of the brain B. The medical device system 100 generallyincludes a device 120 capable of being implanted in a patient 110 andcoupled to one or more therapy delivery elements 130 and/or one or moremonitoring elements 140 via one or more conduits 150 or in a wirelessmanner. The therapy delivery elements 130 deliver treatment therapy to apatient's nervous tissue (e.g., the brain). Likewise, the monitoringelements 140 monitor or sense one or more characteristics of nervoustissue (e.g., brain, spinal cord) or of other organ and can be the samedevice as the therapy delivery elements 130. Therapy delivery elements130 or monitoring elements 140 may comprise one or more stimulationelectrodes and may be implanted, by conventional stereotactic surgicaltechniques, into a structure of the brain such as the thalamus, theinternal capsule, the globus pallidus, the subthalamic nucleus, or otherneural structure. Alternatively or additionally, therapy deliveryelements 130 or monitoring elements 140 may comprise one or moredelivery tubes (e.g., catheters). Therapy elements 130 and/or 140 may besurgically implanted through a hole in a patient's skull and a remainingportion of the lead may be implanted between the patient's skull andscalp. Each therapy element may include one or more electrodes along itsbody.

As used herein, the term “therapy elements” refers generally to thestructures of the medical device system providing therapy and/ormonitoring a condition. For example, therapy elements include therapydelivery elements 130 and/or monitoring elements 140. As anotherexample, discussed herein, therapy elements may include catheters (ortubes) for delivering fluid to the patient or receiving fluid from thepatient.

The implantable device 120 may continuously or intermittentlycommunicate with an external programmer 123 (e.g., patient or physicianprogrammer) via telemetry using, for example, radio-frequency signalsand having a coil 124 and a lead 122 coupling the programmer 123 withthe coil 124. The external programmer 123 may be any general-purposecomputing device (e.g., personal computer, hand-held device, etc.)having an operating system configured with custom external systemapplication software.

In an embodiment where the medical device system 100 includes a brainstimulation system, the medical device system 100 delivers electricalstimulation to the brain through the therapy delivery elements 130. Inthe event that the medical device system 100 also utilizes closed-loopfeedback control, the medical device system 100 monitors BrainElectrical Activity (BEA) or some other signal from the monitoringelements 140, conditions the brain signals for processing, determinesthe onset, presence, and/or intensity of any neurological event,configures the parameters for delivering electrical stimulation throughthe therapy delivery elements 130 if any should be provided.

The medical device system 100 also includes an implantable interfacesystem interconnecting therapy elements 130 and/or 140 with the conduits150. FIG. 2 depicts an embodiment of an interface system 200 for theimplantable medical device system. The interface system 200 may beconstructed of titanium or other suitable, bio-compatible materialhaving necessary physical characteristics to mate with the patient'sskull. In an embodiment, the interface system 200 comprises 16 sets oftherapy elements 205 and 5 conduits 210. As will be discussed below,interface system 200 is contained within a sealed housing 215 so as toprovide a fluid-tight seal between components within the interfacesystem and the patient. The housing 215 may be fastened together withfasteners 220 and may include an opening covered by a membrane 240,impermeable to fluids (discussed below with respect to FIG. 8).

FIG. 3 depicts an embodiment with a circular interface system 300,however, the interface system may take any number of geometric shapesdepending on the particular application, location of implant, and/ordesign considerations. The interface system may include a plurality ofconduits 310 delivering electrical stimulation energy from a signalgenerator, which through a plurality of therapy elements 305 deliverstimulation energy to desired regions of the body (and/or monitoring acondition). Optionally, the interface system may have a key to enableadjustment of the activated therapy elements (discussed further herein).As discussed, the interface system enables the use of a surplus oftherapy elements to monitor/treat the same site (in the case ofelectrode migration), or to monitor/treat different sites within thespatial domain of the therapy elements (through the “spare” therapyelements), both of which is achieved without the need for additionalsurgical procedures and devices.

Also, as used herein, the term “conduit” refers generally to thestructures of medical device system that interconnects the implantabledevice to the interface system. For example, conduits may be conduits310 that provide/receive electrical signals between the implantabledevice and the interface system. As another example, discussed herein,conduits may include catheters (or tubes) for delivering or receivingfluid between the implantable device and the interface system.

FIGS. 4 and 5 illustrate an embodiment where the interface system isconfigured to be positioned adjacent a skull of a patient. Depending onthe application, the interface system may be placed over the skull,subdurally, or within a cavity formed in the skull. The interface systemmay be fixated to the skull through a variety of known techniques. Forexample, the interface system 403 may be configured to be partially (orcompletely) spaced in a cavity 443 formed in a patent's skull 447 (withappropriate modification to cavity 443). The interface system 403 may beattached to the patient's skull 447 and sealed to provide a fluid-tightseal between the interface system 403 and the patient's skull 447, duramater, brain, and scalp. The interface system 403 may include therapyelements 463 (shown in dotted line) for providing therapy (eitherelectrical stimulation or drug delivery or both) positioned within thepatient's neurological tissue 465. The interface system 403 may containother components to provide additional functionality, for example, suchas a control mechanism, a microprocessor, a communication mechanism,and/or a power source (not shown) set forth in U.S. Pat. No. 6,560,486.

The interface system 403 may be configured so as to comport with thephysical contours of the patient's skull. For example, in the embodimentwhere the interface system 403 is implanted within a cavity 443 withinthe patient's skull, the interface system 403 may have an inner wallsurface that is substantially aligned with a surrounding inner surfaceof the patient's skull. Such alignment simulates the original physicalsurroundings of the patient's brain to avoid trauma thereto. If desiredfor a particular application, dura mater may be removed and the innerwall of the interface system may be placed in direct contact with thesubject's cerebral spinal fluid/brain, for example, as described in U.S.patent application Ser. No. 11/339,108 filed on Jan. 25, 2006 andentitled “Anchoring of Medical Device Component Adjacent a Dura of theBrain or Spinal Cord.”

FIG. 6 depicts an embodiment of specific components of an interfacesystem 600. The interface system 600 provides an interface for themedical device system and generally comprises a top cover 605, anoptional spring washer 610, a top plate 615, a middle plate 620, abottom plate 630, a bottom cover 640, and connecting elements 625 eachproviding an electrical connection between a conduit and a therapyelement. In the embodiment, each therapy element is associated with acontact point in the top plate 615. Each conduit, at one end, is coupledto a contact point in the base plate 630 and, at the opposite end, iscoupled to a signal generator.

As can be appreciated, FIG. 6 depicts an embodiment of the specificcomponents of an interface system 600. As depicted, the interface system600 has a first plate that is coupled to one or more conduits via one ormore first plate contact points. The second plate is coupled to one ormore therapy elements via one or second plate contact points. One ormore connecting elements are provided wherein each connecting elementprovides a robust electrical connection between a selected conduit and aselected therapy element. In particular, the connecting element providesphysical contact between the first plate contact point associated withthe selected conduit and the second plate contact point associated withthe selected therapy element. A spring mechanism may also be providedwithin the interface system to ensure adequate electrical connectionprovided by the connecting elements. Further, the top cover 605 and thebottom cover 640 may together form a housing that may provide theinterface system with a fluid-tight seal. As can be appreciated, the topcover may include an opening that is sealed with a flexible membrane soas to provide access to the first plate.

To illustrate the operation of the interface system 600, FIG. 7 depictsan embodiment with specific components of the device, namely the topplate 615, the middle plate 620 (optional), and the bottom plate 630.The bottom plate 630 provides a geometry that enables connection of upto 16 therapy elements 705 (see also elements 130 and 140 of FIG. 1) tofive conduits 710 (see also, conduits 150 of FIG. 1). As can beappreciated, however, some other number of therapy elements 705 and/orconduits 710 may be provided. Each therapy element 705 may be attachedto the bottom plate 630 in a manner that provides connectivity to aplurality of base contact points 715. As depicted, the bottom plateprovides connection for each therapy element 705 to five base contactpoints 715, each of which functions to provide selectable connection toa corresponding conduit 710. Similarly, the top plate 615 provides ageometry that enables each of the conduits 710 to be connected to aplurality of top contact points 720. As depicted, the top plate providesconnection for each conduit 710 to sixteen top contact points 720, eachof which functions to provide selectable connection to a correspondingtherapy element 705. The base contact points 715 and top contact points720 geometrically coincide. The interface system enables selectiveconnections between certain base contact points 715 and top contactpoints 720 in order to produce a desired combination of connectionsbetween certain therapy elements 705 and conduits 710. For illustration,as depicted, connections 1 a, 11 b, 13 c, 3 d, 4 e, and 15 e are made bythe interface system, with all other potential connections between basecontact points and top contact points not enabled. This configurationconnects therapy element 1 to conduit a, therapy element 11 to conduitb, therapy element 13 to conduit c, therapy element 3 to conduit d, andtherapy elements 4 and 15 are both simultaneously connected to conduite.

One skilled in the art will appreciate that there are many known ways tocommunicatively connect a desired subset of base contact points 715 totop contact points 720, and the means for connection may vary dependingupon the application and may include, but are not limited to, galvanicconnections such as may be provided by a connecting wire or solid staterelay, optical connections, or fluidic connections such as may beprovided by one or more valves. The interface system may enable easyselection of the desired connections, and ensure that the connectionsare robust. Techniques for selecting desired connections may include,for example, any of the following:

-   -   a. mechanical means, such as by pressing one or more buttons        that operate to toggle (or otherwise modify) the state(s) of        particular connection(s);    -   b. use of telemetry from a programmer device (e.g., using        infrared, radio-frequency, or ultrasound) to toggle connections;        or    -   c. use of an optional middle connecting plate 620, which may be        inserted between bottom plate 630 and top plate 615, wherein the        connecting plate 620 essentially serves as a mechanism to        position one or more connecting pins through apertures        geometrically aligned with top and bottom contact points, in        order to provide connections between desired contact points when        the plates 615, 620, and 630 are assembled together.

Thus, FIGS. 6-7 disclose details of embodiments of an interface systemthat allows a health care provider to adjust which conduits areconnected to which therapy elements. It should be noted that theconnecting pins 625, while depicted as elongated, may be any other shapesuch as spherical. Thus, numerous variations are possible and will beappreciated in light of the present disclosure.

Turning to FIG. 8, a simplified exploded cross-sectional view of anembodiment of an alternate interface system is depicted. As depicted, aself-sealing membrane 806 or alternatively a sliding plate is positionednext to an access template 808, which is depicted as being biased. Aswill be discussed, the biased access template 808 may include a numberof apertures 945. A top plate 820 is positioned below the biased accesstemplate 808 and includes a plurality of controller extensions 821. Abottom plate 830 is positioned below the top plate 820 and may include anumber of contact points 822. It should be noted that, as discussedabove, the elements depicted in FIG. 8 typically are mounted in ahousing that is configured to support the various components in theirappropriate positions relative to each other. It should be noted thatthe depicted arrangement is merely exemplary. For example, the membrane806, which may be silicone or some other suitable material, may bemounted directly to the housing. As can be appreciated, the membrane 806can act to prevent the influx of tissue and fluids that might otherwiseblock the apertures in the biased access template 808 (discussed below).

FIGS. 9 a and 9 b illustrate the biased access template 808 positionedabove the top plate 820. As depicted, the biased access template 808includes a plurality of apertures 945 and when the biased accesstemplate 808 is aligned with the top plate 820, the apertures 945coincide with the controller extensions 821. When the biased accesstemplate 808 is in a first position as shown in FIG. 9 a, however, theapertures 945 do not align with the controller extensions 821. Thus, toalign the apertures 945 with the controller extensions 821, the biasedaccess template 808 may be moved from a first position as depicted inFIG. 9 a to a second position as depicted in FIG. 9 b. However, alocking feature 940 may first need to be actuated or otherwisepositioned in a non-locking position.

Turning to FIG. 10 a, once the access cover 808 is positioned in thesecond or aligned position, a tool 1175 may be inserted through one ofthe apertures 945 so as to make contact with one of the controllerextensions 821. By pressing on the controller extensions 821, theconfiguration of the interface system may be adjusted. The upper-mostpart of each controller extension 821 may be designed to allow stablecoupling with the tool 1175 to avoid slippage. Referring to FIGS. 10 band 10 c, another arrangement is depicted wherein tracks with a rack andpinion arrangement may be utilized to slide a plate with apertures overanother to align the holes. It will be appreciated that any number ofarrangements may be utilized to bias and move the access plate. Forexample, a spring mechanism may be utilized to align the plate betweenopen and closed positions.

FIG. 11 depicts an embodiment of a system for protecting the interfacesystem. A gear mechanism 1081 may be utilized to engage with teeth 1084.Rotation of the gear 1081 causes the cover plate 1080 to move relativeto the top plate 1082. A track 1086 helps to maintain the matingcomponents. As one skilled in the art may appreciate, the top plate andthe bottom plate of the interface system may utilize tracks to stabilizeand govern the movement of the cover plate. Optionally, as depicted, thecover plate may have a lip that engages with a track that may be, forexample, on the top plate.

Referring to FIG. 12, a top plate 820 is depicted as positioned abovethe bottom plate 830. As can be appreciated, each of the controllerextensions preferably will be aligned with a contact pad 945 positionedon the bottom plate 830. By activating the controller extension 821, anelectrical connection may be made.

Referring back to FIGS. 9 a and 9 b, it should be noted that the biasedaccess template 808 is depicted as being biased toward the firstposition (depicted in FIG. 9 a) by biasing element 950. Various methodsof biasing may be used, such as, but without limitation, a springelement, a compressible cylinder or the like. As the use of a biasingelement is known, no further discussion will be provided.

In an alternative embodiment, an access template may be provided that isnot biased. Regardless of the existence of the biasing element, theaccess template may be locked in a first position with a locking feature940 and to move the access template to the second position may requirethe pressing of one or more buttons so as to allow unlocking of theaccess template and allow it to translate to the second position. As canbe appreciated, the use of more than optional locking feature 940provides additional security that incidental contact will not allow theaccess template to translate into an aligned position. Further securitymay be provided by requiring the insertion of one or more keys (notshown) so as to unlock the one or more locking features 940. Inaddition, multiple access templates may be provided and two differenceaccess templates may be configured so that the access templates are eachtranslated in different directions in order to align the apertures withthe controller extensions. Thus, looking at FIG. 9 a, a second accesstemplate 808 (not shown for purposes of clarity) could be provided thattranslated in a different direction than the access template 808 that isdepicted. Each of the access templates may include a separate anddistinct locking feature or a single locking feature may be used formultiple access templates.

It should be noted that, similar to the embodiment depicted in FIG. 7,multiple controller extensions 821 may be connected to a single conduit.In an embodiment as depicted in FIG. 13, a conduit 1320 may link to themultiple controller extensions 821. Depending on the position of thelinked controller extensions, this allows the conduit 1320 toelectrically connect to multiple contact pads 945, each of which may beconnected to a separate therapy element. As can be appreciated,displacing the controller extension 821 allows an electrical connectionbetween contact pads 945 with conduit 1320.

FIGS. 14 and 15 illustrate an embodiment of how depressing thecontroller extension 821 can create the electrical connection. Lookingfirst at FIG. 14, a connector housing 1405 is mounted to the top plate820 and the controller extension extends above the top plate 820. Aconnector pin 1410 is positioned in the connector housing 1405 and isbiased in an open position by the biasing element 1420. As depicted, aconduit 1322 is connected to the biasing element 1420. Positioned belowthe connector housing 1405 is a contact pad 945 that is supported by thebottom plate 830 and is connected to a therapy element 1440.

FIG. 15 removes the top and bottom plates 820 and 830 for ease ofillustration.

Pressing down on the controller extension 821 causes the connector pin1410 to translate until in comes into contact with the contact pad 945.The connector pin 1410 may be held in position by a detent that preventsthe connector pin 1410 from translating back to the open position untilthe controller extension 1410 is pressed again (in a manner similar tooperation of a retractable pen). Alternatively, the connector pin may berotatably supported by a thread and contact between the connector pin1410 and the contact pad 945 may be accomplished by rotating theconnector pin 1410 in a manner similar to how a screw is used.

It should be noted that if a translating connector pin 1410 is used thatis similar to what is disclosed in FIGS. 14-15, it may be beneficial toreduce the distance the conduit 1322 translates when the connector pintranslates to the open position. Therefore, FIG. 16 illustrates anembodiment wherein the conduit branch 1322 is connected to an upperportion 1422 of the biasing element 1420. As can be appreciated,minimizing the amount of translation of the conduit 1322 can be usefulin increasing the robustness of the design and in avoiding unnecessarywear.

As can be appreciated, the ability to control which conduits are coupledto which therapy elements helps minimize the need for surgicalreplacement or repositioning of therapy elements in the event that theybreak down, migrate or the patient's monitoring or therapy target(s) orcondition changes after the therapy elements are implanted. Instead, theconduits may be coupled to alternative therapy elements.

Thus, in the above two embodiments, connectors from one plate makecontact with another plate only when deployed. The deployment of theconnectors may be achieved through a variety of techniques including,but not limited to, spring mechanisms (that operate in a manner similarto that of retractable ball-point pens), magnets, radio-frequency tags,ultrasound, and/or infrared light. Where a spring mechanism is utilized,the spring mechanism may be depressed with a “pointer” (e.g., tool 1175of FIG. 11) (the top plate has openings over each spring mechanism) thatis inserted through the scalp using a needle-like tool. The upper mostpart of the upper portion 1422 of the biasing element 1420 may bedesigned to allow stable coupling with the tip of “pointer” to avoidslippage. The person changing the connections will have a “template”plate which is identical to the top one mounted in the skull and whichwill be placed over the scalp and aligned with the one underneath it.Fiducials made of plastic, noble metals or ink (“tattooed”) detectableon the scalp (visible, palpable or amenable to imaging) defining theboundaries of the skull mounted interface, will allow precisesuperposition of the template over the top skull mounted plate. The samescheme may be used with a pencil magnet except that in this case thescalp will not be pierced.

It should be noted that in addition to electrical connectors, othertypes of connectors such as optical connectors can be similarlyconfigured. As can be appreciated, a first light pipe with a pluralityof passageways could be aligned with a plurality of light pipes and byselectively connecting the first light pipe to one of the plurality oflight pipes, optical signals could be routed as desired.

In an embodiment, the housing of the interface system may include 5holes in the four corners and center of the outer surface of theskull-mounted connector, where each hole has a pin which is removableand protrudes from the closed scalp. An indelible biocompatible ink(such as a tattoo) or some other fiducial may be used to mark the scalparound the protruding pins and after this has been done, the pins may beremoved. These scalp fiducials may be subsequently used to guidealignment with the access template, which will be positioned within theinterface system. It should be noted that some other number of fiducialsmay be used, however, at least three fiducials is preferred so as toensure a proper orientation.

As noted above, while electrical signals can be recorded and electricalstimulation may be used to treat a patient, pharmaceutical compounds andmedicaments may be beneficial in treating a patient. In addition, theability to collect fluids from various portions of the patient's brainmay be helpful in detecting and analyzing the patient's condition.

FIG. 17 illustrates an embodiment of an interface that may be used toadjustably delivery or collect substances to and from the patient'stissue such as a brain. Flow module 1705 may be positioned in a mannersimilar to corresponding structure depicted in FIG. 8 (except bias plateand protective member are not depicted in FIG. 17). However, as can beappreciated, the bottom plate is not required to direct the flow ofsubstances. As depicted, a fluid enters the module 1705 through conduit(or inlet tube) 1710. Depending on the configuration of the valves 1720a-1720 e, fluid is directed out the therapy elements (or delivery tubes)1715 a-1715 e. It should be noted that while the flow of fluid isdepicted as proceeding from the inlet tube 1710 toward the deliverytubes 1715, a reverse direction of flow is also contemplated.Furthermore, while FIG. 17 depicts a single source supplying a pluralityof delivery tubes, in an alternative embodiment the delivery tubes couldbe distinct sources of fluids that supply the inlet tube 1710. As can beappreciated, this could be used to collect samples of fluid from thepatient and could also be used to adjust the delivery of a compoundfluid to a single port or catheter. The valves in FIG. 17 are depictedin three configurations, closed (as shown by valve 1720 c), partiallyopen (as shown by valves 1720 a, 1720 b and 1720 e) and fully open (asshown by valve 1720 d).

FIGS. 18 a-18 c illustrate similar configurations without the module1705. It should be noted that while the valve 1720 is depicted as beingclosed when button 1721 is depressed, the reverse is also contemplated.

FIGS. 19 a-19 d illustrate embodiments of valves 1720 that include anouter wall 1910, a core 1920 that includes a fluid passageway 1925 andmultiple tubes 1710, 1715, 1716. As can be appreciated, FIGS. 19 a-19 dillustrate the core 1920 being rotated around in different positions sothat the fluid passageway 1925 couples different tubes together. Asdepicted in FIG. 19 d, the flow from inlet tube 1710 is evenlydistributed to delivery tubes 1715, 1716. In an embodiment, thedepressing of the button 1721 (FIGS. 18 a-c) may cause the core 1920 torotate (through known techniques such as “helical” or other guidedthreading to produce rotation) so that different tubes are coupledtogether (or so that no tubes are coupled together). In an alternativeembodiment, the core 1925 may be configured in the desired position wheninstalled. In another alternative embodiment, translation of the button1721, which may include rotation, may allow for the rotationalorientation of the core to be adjusted. Preferably the orientation ofthe core will be apparent and to aid in this matter, an asymmetric key(not shown) may be required to translate the button.

While FIGS. 19 a-19 d illustrate a full coupling between the fluidpassageway 1925 and the tubes, in an alternative embodiment as depictedin FIG. 20, the fluid passageway 1925 may provide for a reduce flow rateto one of the tubes versus the other tubes. In an embodiment, the flowfrom tube 1710 may be distributed to delivery tube 1715 in a ratio of9:1 versus delivery tube 1716. As can be appreciated, if the deliverytube 1715 supplies other delivery tubes than such a flow distributionmay be useful to ensure relatively consistent flow is provided to eachdelivery tube. The varying flow rate may be achieved with fluidpassageways 1925 having differing diameters and/or offsetting of thefluid passageways 1925 from corresponding tubes 1710, 1715, and 1716.

It should be noted that FIG. 17 illustrates a number of valves inseries. In an embodiment it may be desirable to always direct flowthrough each valve but to control whether the flow is directed out theassociated delivery tube. To provide such control, in an embodiment theflow passageway 1925 may be configured as depicted in FIG. 21. In thedepicted position the flow would pass from inlet tube 1710 to deliverytube 1715 but would not be directed toward delivery tube 1716. Byrotating the orientation of the flow passageway 1925 180 degrees,however, fluid may be directed toward the delivery tube 1716.

It should be noted that multiple flow passageways may be provided in thecore 1920, with each flow passageway stacked on top of another flowpassageway. In such a configuration, depressing the button 1721 willalign a different flow passageway with associated tubes. This depressioncan toggle the state of an associated valve, for example, by causing arotation to allow flow passage in any number of combinations.

As depicted in FIG. 22, multiple flow modules 1705 may be used together.As can be appreciated, this allows delivery of multiple substances tosimilar locations.

FIG. 23 illustrates an alternative embodiment of a complex flow module1705. In an embodiment, each of the conduits (or inlet tubes) 1710a-1710 c can be configured to direct fluid to each of the therapyelements (or delivery tubes) 1715 a-1715 e, depending on theconfiguration of the valves 1720. In an embodiment, each of theoutlet/delivery tubes 1715 is fed by the three inlet tubes 1710 a-1710c. Thus, as depicted, the fluid exiting delivery tube 1715 a includesfluid received from valves 1720 a, 1720 d and 1720 e. Flow may passthrough each valve 1720 even if each valve 1720 is not used to directflow toward a delivery tube 1715. Thus, for example, flow from inlettube 1710 c provides flow to open valve 1720 c even though valve 1720 bis closed.

FIG. 24 illustrates a simplified embodiment of a fluid delivery system.Plate 2410 may be moved utilizing a mechanism such as, for example, arack and pinion or microstepper motors. The pump 2405 includes a firstreservoir 2406 and a second reservoir 2407, each with a differentmedicament stored within the reservoir. By sliding the plate 2410clockwise, ports 2415 can be aligned with pump tubes 2420. As can beappreciated, this allows for a graduated response. In a first positionno fluid is provided. In a second position, a single pump tube 2420 issupplying fluid from a first reservoir 2406. In a third position, twopump tubes are supplying fluids from a first reservoir and one pump tubeis supply fluids from a second reservoir 2404. Thus, such a systemprovides a tiered response. Those skilled in the art would appreciatethat plate 2410 may be moved clockwise or counterclockwise. Also, thenumber and diameter of ports 2415 and the distances from their center tothe outer edge of each set of tubes 2420, and the ratio of diameter of2415 to diameters 2420 may be modified to so that a large number ofadjustments may be effected according to the application.

FIGS. 25 a and 25 b illustrate another aspect that may be used inaccordance with the present invention. These embodiments may be therapyelements where selectivity of fluid delivery is achieved along the bodyof the therapy elements. A tube 2510 is provided with a plurality ofports 2515 that are closed (i.e., not exposed to fluid) and a number ofports 2516 that are open (i.e., exposed to fluid). A slidable plate 2520is positioned within the tube 2510 and the position of the slidableplate 2520 may be adjusted with member 2530. Member 2530 may, forexample, be associated with a controller extension (discussed above). Bytranslating the slidable plate 2520, more or less of the ports may beblocked or unblocked. Thus, such a system may provide for more finetuned control over delivery of fluids. As can be appreciated, theslidable plate 2520 can be configured so that it blocks a first set ofports in a first position, blocks a second set of ports in a secondposition and blocks a third set of ports in a third position.

Although ports are shown in a single line for simplicity, it will beappreciated that the ports 2515 and 2516 may be in any direction alongthe tube 2510. For example, there may be an array of ports 2515 and 2516along the entire surface of tube 2510. Moreover, plate 2520 mayalternatively be a hollow cylinder to which drugs arrive via a conduitand then plate 2520 delivers fluid only to the adjoining port that itengages. Even further, there may be multiple plates 2520 in tube 2510 toprovide additional flexibility. Alternative embodiments are alsopossible, for example, the embodiment of FIG. 25 c having an outercatheter 2560 having a plurality of ports 2564 and a rotatable innercatheter 2562 having a plurality of ports 2666. Once inserted within theouter catheter 2560, the inner catheter 2562 may engage or disengageports.

In an embodiment, the length of the slidable plate 2520 may be increasedso that the slidable plate 2520 extends a substantial length down thetube 2510. In such an embodiment, the slidable plate 2520 may include apattern of openings that matches a pattern of ports in the tube 2510such that moving the slidable plate 2520 a small distance causes asubstantial change in the number of ports that open or blocked by theslidable plate. As can be appreciated, the ports may be evenly orvariable spaced and in a closed position, none of the openings of theslidable plate will be aligned with the ports in the tube 2510.

It will be appreciated that any number of configurations may beimplemented in accordance with the invention. For example, as discussed,the interface system (and corresponding layout of the associatedcomponents) may take the form of any number of geometric shapes.Moreover, connecting pins 625 may take the form of any number ofconnecting elements for providing electrical connectivity. In anembodiment, the controller extensions may be translatable via theapplication of magnet force. As can be appreciated, such a configurationwill allow the individual adjusting the delivery of stimulation toadjust which electrodes are connected to which conduits without the needto pierce (with a “needle”) or make a small incision in the patient'stissue.

It should be noted that the control of the position of the valves andposition of the connector extension 821 may be automated and controlledvia a controller, which may be programmed via a wireless manner with aprogrammer such as a physician programmer. The advantage of usingmechanical controlling is that no electrical power is required to changethe configuration.

The interface system disclosed above provides the ability to selectivelyidentify those therapy elements that should be operable by the medicaldevice system. The therapy elements may be selected initially duringimplant but may also later be modified via use of the key and/or througha minimally invasive procedure. For example, in the embodiment of acircular interface system (FIG. 3), the key (keyhole not shown) mayserve as a rotatable dial to facilitate the precise alignment (andsubsequent adjustment) between the top plate and base plate.

Moreover, the ability of the interface system to connect more than oneimplanted element in tissue together into a single connection in thedevice (e.g., as depicted in FIG. 7 for therapy elements 4 and 15connected to conduit e), enables the delivery of therapy to multiplesites using a single device output. In the aforementioned example, ifthe therapy modality is electrical stimulation, then the therapyelements (i.e., stimulation contacts) 4 and 15 may be “tied together” bythe interface system and treated as a single cathode or anode fordelivery of stimulation current. Similarly, when used for communicationin the reverse direction (when the implanted elements can function assensors) this feature enables the device to monitor an aggregate signalderived from a plurality of sensors in spatially economic andcost-effective ways, since the number of required device input ports andassociated hardware (amplifiers, A/D converters, etc.) may be reduced.The “tying together” of multiple contacts may be applied, for example,to seizure detection and localization of the focus/foci from which theyoriginate in the brain. By way of illustration, suppose for example,that a subject has 64 implanted contacts, with 32 of them located in theleft hemisphere (8 contact electrode leads placed in each of theanterior, medial, and posterior temporal lobe, and an 8 contact leadplaced in the frontal lobe) and 32 in the right hemisphere (homologouslyplaced). Rather than require an equal number of device input ports andassociated hardware (in this case, 64) to condition and analyze allavailable signals, the approach described herein reduces the amount ofhardware required in the device, in embodiment, to only 8 device inputports, while retaining the ability to access any subset, or the entireset of the elements implanted within the tissue. In particular, supposethat the patient has an implanted seizure monitoring device which islimited to 8 inputs but there are 64 sensors. Since seizures may bedetected in an aggregate signal, which functions as a weighted sum ofvoltage levels from the individual sensor locations, one may use a 64×8interface system and connect each of the eight 8-contact electrodeleads, each corresponding to a different brain region, to produce eightrespective lead-aggregate interface system connections to the ports ofthe seizure monitoring device (using one port for each aggregated brainregion signal covered by its respective lead). Once the patient has beenmonitored so as to capture a sufficient number of representativeseizures, the process of more precise localization (identification ofthe sites/sensors most frequently involved in seizures) may begin. Thismay be accomplished via the interface system by disabling those leadsthat are not associated with the brain region(s) from which seizurebegin. This process may be repeated until the lead or lead(s)corresponding to the seizure focus/foci are determined, after which theprocess can be refined to select relevant subsets of individual sensorsfrom the remaining leads, which can be isolated and individuallymonitored until the optimal set of sensors is determined. This optimalsubset of sensors, and the procedure used to identify them, can alsoprovide improved efficacy of therapy via selective delivery to theprecise site(s) from which seizures originate.

The usefulness of the invention should be apparent to one skilled in theart. The use of any and all examples or exemplary language herein (e.g.,“such as”) is intended merely to better illuminate the invention anddoes not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

The present invention has sometimes been described in terms of preferredand illustrative embodiments thereof. Numerous other embodiments,modifications and variations within the scope and spirit of the appendedclaims will occur to persons of ordinary skill in the art from a reviewof this disclosure.

1. An implantable interface for a medical device system comprising: (A)a top plate (B) a base plate; (C) a plurality of therapy elements, eachtherapy element being associated at least one base contact point in thebase plate; (D) a plurality of conduits, each conduit having a first endcoupled to at least one top contact point in the top plate and a secondend capable of being coupled to a monitoring or therapy device; and (E)at least one connecting element selectively positionable between the topplate and the base plate to provide electrical connection between aselected conduit and a selected therapy element.
 2. The interface ofclaim 1, wherein the connecting element is a pin.
 3. The interface ofclaim 1, wherein the connecting element is a sphere.
 4. The interface ofclaim 1, wherein the connecting elements provide electrical connectionbetween the at least one top contact point associated with the selectedconduit and the at least one base contact point associated with theselected therapy element.
 5. The interface of claim 1, wherein the eachtherapy element is a sensor.
 6. The interface of claim 1, wherein eachtherapy element is associated with a lead implantable within a brain ofa patient, the lead having a proximal end coupled to the base plate anda distal end having the associated therapy element to sense electricalsignals or sense electrical signals.
 7. The interface of claim 1,wherein each therapy element is associated with a lead implantablewithin a brain of a patient, the lead having a proximal end coupled tothe base plate and a distal end having the associated therapy element todeliver electrical stimulation within the brain of the patient.
 8. Theinterface of claim 1, further comprising a middle plate between the topplate and the base plate to facilitate positioning of the connectingelements.
 9. The interface of claim 1, further comprising a cover forthe interface system providing a hermetic seal.
 10. The interface ofclaim 1, further comprising a spring mechanism within the interfacesystem to facilitate electrical connection provided by the connectingpin.
 11. The interface of claim 1, further comprising a key.
 12. Animplantable interface for a medical system, comprising: a housing; afirst plate positioned in the housing and including a plurality ofcontroller extensions, the controller extensions configurable between anopen position and a closed position; a second plate positioned in thehousing and including a plurality of contact pads; a conduit coupled toat least one of the plurality of controller extensions; a plurality oftherapy elements coupled to the plurality of contact pads; and aflexible membrane mounted to the housing and configured to providesealed access to the first plate.
 13. The implantable interface of claim12, further comprising an access template positioned to occlude thefirst plate and configured to translate between a blocking position andan access position, whereby the access template may selectively blockaccess to the plurality of controller extensions on the first plate. 14.The implantable interface of claim 13, wherein the access template isbiased toward the blocking position.
 15. The implantable interface ofclaim 13, wherein the access template includes a locking featureconfigured to selectively allow translation of the access template. 16.The implantable interface of claim 13, wherein the controller extensionsare configured to switch between an open position and a conductingposition in response to a tool pressing on the controller extension. 17.The implantable interface of claim 13, wherein the conduit comprises 5conduits and the plurality of therapy elements comprises 16 outputleads, and wherein each of the five conduits may be selectively coupledto each of the 16 output leads.
 18. A method of adjusting an implantedinterface, comprising: (a) aligning a template with at least threefiducials on a person's head; (b) translating an access template into anaccess position; and (c) adjusting at least one controller extension.19. The method of claim 18, wherein the translating in (b) comprises:(i) disengaging a locking feature to unlock the access template; and(ii) sliding the access template from a block position to the accessposition.
 20. The method of claim 19, wherein the unlocking in (i)comprises: (1) inserting a key to unlock the locking feature; and (2)pressing a button to disengage the locking feature.
 21. The method ofclaim 18, wherein the adjusting in (c) comprises: (i) moving a firstcontroller extension from an open position to a conducting position; and(ii) moving a second controller extension from the conducting positionto the open position.
 22. The method of claim 21, wherein the moving ofthe first extending in (i) comprises: (1) inserting a tool through apatient's scalp; and (2) pressing on the first extension connector so asto actuate a switch in position of the first controller extension. 23.An implantable interface for a medical device system comprising: (A) atop plate (B) a base plate; (C) a plurality of therapy elements, eachtherapy element being associated with at least one base contact point inthe base plate; (D) a plurality of conduits, each conduit having a firstend coupled to at least one top contact point in the top plate and asecond end capable of being coupled to a signal generator; (E) a middleplate positioned between the top plate and the base plate; (F) at leastone connecting element selectively positionable in the middle plate toprovide connection between the top contact point associated with theselected conduit and the base contact point associated with the selectedtherapy element; (G) a spring mechanism within the interface system tofacilitate electrical connection provided by the connecting element; and(H) a cover for the interface system providing a fluid-tight seal.